Babesia felis

Babesia felis

<p align="CENTER"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: large;"><i><b>Babesia felis</b></i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: large;"><b> Davis, 1929</b></span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>ETYMOLOGY:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> for Dr. Babès and </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (cat)</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>SYNONYMS:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesiella felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (Davis, 1929) Carpano, 1934; </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Nuttallia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (Davis, 1929) Krylov, 1974; </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Nuttallia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> var </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>domestica</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Jackson and Dunning, 1937; </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Nicollia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (Davis, 1929) Krylov, 1981.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>HISTORY:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> was first described as a parasite of the domestic cat by Jackson and Dunning in 1937; these authors gave it the name </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Nuttallia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (a synonym of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">) </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> of the variety </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>domestica</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">. The variety designation was to separate it on the basis of its pathogenicity from a previously described, but morphologically, indistinguishable </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> described by Davis in 1929 from a Sudanese wild cat (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Felis ochreata</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">) that was not pathogenic when inoculated into domestic cats.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>GEOGRAPHICAL DISTRIBUTION:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Reports of feline babesiosis due to </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> are restricted almost exclusively to Zimbabwe and South Africa (Futter and Belonje, 1980a). The original isolate from a sudanese wild cat was established experimentally in domestic cats (Davis, 1929).</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>LOCATION IN HOST:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> The only cell in the body parasitized by merozoites of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> spp. are the red blood cells.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>PARASITE IDENTIFICATION:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> The merozoites of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> that occur within the red cell are small, faintly blue staining organisms that have a dense chromatin granule. Many forms have a large central vacuole which gives them the appearance of being ring shaped. Single organisms measure less than 1 m to 2.5 m in diameter. Division of the organisms produces pairs and cross-shaped tetrads of organisms. The ultrastructure of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> was described by Dennig and Hebel (1969).</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>LIFE CYCLE:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> The life cycle of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> has not been elucidated, but it is believed that ixodid ticks serve as the biological vector of the parasite. In 1937, Dr. McNeil reported that he reared larval and nymphal ticks from an adult female </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Haemaphysalis leachi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> that was removed from a cat with babesiosis. Neither the eggs nor the nymphs that developed transmitted the disease to cats upon which they were fed. The bottle containing the imago ticks was then broken and the ticks escaped, and Dr. McNeil without evidence or proof was convinced that they were the source of babesiosis that developed in his own household cat. There have been no other studies on the transmission of feline babesiosis.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> If, as suspected, the life cycle utilizes ixodid ticks that have fed on cats, sporozoites will develop within the salivary glands of the tick. Within the tick there is the possibility that the different stages, larvae, nymphs, and adults, may differ in their ability to transmit the infections, and further work is needed to clarify this in the case of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Once in a cat, the merozoites infect blood cells, dividing and multiplying to form stages infecting new blood cells. In cats that have been inoculated with blood from other cats, parasites are evident within the peripheral blood within 1 to 2 days after inoculation (Futter and Belonje, 1980b). It is not known how long after the appearance of organisms in the blood that infectivity for the tick vector might develop.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>CLINICAL PRESENTATION AND PATHOGENESIS:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Cats are typically admitted with a history of inappetence, lethargy, and weakness or morobund. Mucous membranes may be pale, and tachycardia and tachypnea (perhaps dyspnea) consistent with profound anemia may be noted. Icterus is seldom seen and fever does not seem to typically accompany the disease. (Futter and Belonje, 1980b). In experimentally infected animals, anemia is most severe about 3 weeks after inoculation, and there are significantly lowered hematocrits, hemoglobin levels, and erythrocyte numbers (Futter et al., 1980). Erythrocytes tend to be macrocytic and hypochromic. There are no significant changes in total leukocyte counts initially. In most cases liver function, renal function, and venous blood pH will remain normal (Futter et al., 1981). Without treatment, cats are very likely to die of severe anemia. Of 70 naturally infected cats, 50 recovered, 7 died, 7 were euthanatized (3 were strays, 1 for chronic respiratory disease, 1 for aplastic anemia, and 2 for unstated reasons) and 6 were lost to follow up (Futter and Belonje, 1980b).</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>TREATMENT:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Treatment with primaquine phosphate will often lead to a rapid and successful recovery. In cases of severe anemia and prostration, it may be necessary to also give a blood transfusion followed by primaquine therapy. However, the current effective dose (0.5mg/kg, IM, once) is very close to the lethal dose in cats (1 mg/kg).</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>EPIZOOTIOLOGY:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> It would appear that </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> is a parasite of the cat. There may have been some initial African source of this parasite, but the parasite now seems mainly to affect its domestic host.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>HAZARD TO OTHER ANIMALS:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Specimens of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> considered to be </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> by some workers (Dennig and Brocklesby, 1972) have been found in the blood of a puma, </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Felix concolor</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">, that had been housed in a zoo in Egypt (Carpano, 1934) and in a blood smear from an Indian leopard, </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Panthera pardus fusca</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (Shortt, 1940). As stated above, </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> was first noted in the blood of a Sudanese wild cat (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Felis Ocreata</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">). It would appear that the has been little spread of this parasite between cats and wildlife.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>HAZARDS TO HUMANS:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Although humans have been infected with species of </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> these have been felt to be mainly of bovine and murine types. None have been considered as being due to </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>CONTROL/PREVENTION:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> The disease can be controlled by preventing tick infestations and by treatment of cats that have circulating stages in their bloodstream.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>REFERENCES:</b></span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Carpano M. 1934. Sur les piroplasmoses des carnassiers et wur un noveau piroplasme des félins (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesiella felis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">) chez le puma: </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Felis concor</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">. Bull Min Agr Egypt Tech Sci Ser No 136, 20 pp.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Davis LJ. 1929. On a piroplasm of the Sudanese Wild Cat (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Felix ocreata</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">). Trans Roy Soc Trop Med Hyg 22:523-534.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Dennig HK, Brocklesby DW. 1972. </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia pantherae</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> sp. nov. a piroplasm of the leopard (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Panthera pardus</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">). Parasitology 64:525-532.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Dennig HK, Hebel R. 1969. Licht- und elektronenmikroskopische Untersuchungen an zwei </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia-</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Arten der Feliden. Ztschr Parasitenk 32:95-111.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Futter GJ, Belonje PC. 1980a. Studies on feline babesiosis. 1. Historical review. J S Af Vet Assoc 50:105-106.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Futter GJ, Belonje PC. 1980b. Studies on feline babesiosis. 2. Clinical observations. J S Af Vet Assoc 51:143-146.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Futter GJ, Belonje PC, Van Den Berg A. 1980. Studies on feline babesiosis. 3. Haematological findings. J S Af Vet Assoc 51:272-280.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Futter GJ, Belonje PC, Van Den Berg A, Van Rijswijk AW. 1981. Studies on feline babesiosis. 4. Chemical pathology; macroscopic and microscopic </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>post mortem</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> findings. J S Af Vet Assoc 52:5-14.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Jackson C, Dunning FJ. 1937. Biliary fever (Nuttalliosis) of the ct: a case in the Stellenbosch district. J S Af Vet Med Assoc 8:83-87.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">McNeil J. 1937. Piroplasmosis of the domestic cat. J S Af Vet Med Assoc 8:88-90.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Shortt HE. 1940. </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Babesia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> sp in the Indian leopard, </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Panthera pardus fusca</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (Meyer). Ind J Med Res 28:277-278.</span></span></span></p>